That's a great question, and there are so many cool comments out there to choose from. Here are some ideas:
• "A true friend accepts who you are, but still helps you to become better."
• "Dream big, work smart, and believe in yourself."
• "The expert in anything was once a beginner."
• "Your dream doesn't have an expiration date. Take a deep breath and try again."
• "We are born believing and fearless. Don't lose your sparkle."
• "Surround yourself with people who bring out the best in you."
• "The best way to predict the future is to create it yourself."
• "Life begins outside of your comfort zone."
• "When nothing is sure, everything is possible."
• "The best way to make your dreams come true is to wake up."
I hope you found some cool comments that you like, and I wish you all the best!